Removal of Methylene Blue from Water by BiFeO3/Carbon Fibre Nanocomposite and Its Photocatalytic Regeneration

It is essential to prepare a highly efficient and reproducible adsorbent for purifying industrial dye wastewater. In this work, a novel and efficient BiFeO3/carbon fiber (CCT-BFO) nanocomposite adsorbent was prepared by the template method and through optimizing the preparation process. The morphology, physicochemical properties, and specific surface characteristics of the CCT-BFO were characterized by scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) patterns, Fourier-transform infrared spectrometer (FTIR), and N2 adsorption-desorption isotherm. The CCT-BFO could efficiently remove the Methylene blue (MB) from aqueous solutions, and the adsorption performance is not easily influenced by the environment. The equilibrium adsorption data were fitted to the classical models very well; the maximum capacity of adsorption MB onto the CCT-BFO was higher than many other reported adsorbents and the data of the adsorption kinetics were described by a pseudo-second-order model. Furthermore, the CCT-BFO can be recycled by photocatalytic regeneration. And the constant adsorption capacity was almost retained after recycling five times.